Aquinas: Basic Works

The Arrogance of Humanism

Luther and Calvin on Secular Authority

Treatise on Law

On Law, Morality, and Politics: Edition 2

Summa Theologica (All Complete & Unabridged 3 Parts + Supplement & Appendix + interactive links and annotations)

Medieval Philosophy: A Very Short Introduction

Aristotle's Children: How Christians, Muslims, and Jews Rediscovered Ancient Wisdom and Illuminated the Middle Ages

Questions on Love and Charity: Summa Theologiae, Secunda Secundae, Questions 23–46

Philosophy in the Middle Ages: The Christian, Islamic, and Jewish Traditions, Edition 3

Commentary on Aristotle's Politics

Philovesophy

On Evil

The Treatise on the Divine Nature: Summa Theologiae I 1-13

Maimonides: Life and Thought

SUMMA THEOLOGICA: Including supplement, appendix, interactive links and annotations

Dream of Reason: A History of Western Philosophy from the Greeks to the Renaissance (New Edition)

The Treatise on Human Nature: Summa Theologiae 1a 75-89

Simon of Genoa's Medical Lexicon